Rotary cutting desk corner suspension

Abstract

A rotary cutting deck for a mower includes a cutting deck supported by wheels at three of the four corners of the deck. The other corner of the cutting deck, namely a corner of the deck that is close to the mower, is supported by a corner suspension that lifts upwardly with a biasing force sufficient to elevate that corner of the deck above the ground. This corner suspension takes the place of the caster wheel that would normally support this corner of the deck, and thus permits the deck to be moved closer to the side of the mower, thus reducing overall mower width without decreasing the width of the cutting swath.

We claim:  
     
       1. A rotary cutting deck for a mower, which comprises: 
       (a) a cutting deck having at least one rotary cutting element rotating about a substantially vertical axis in a substantially horizontal cutting plane when the cutting deck and rotary cutting element are in operation, the cutting deck when coupled to the mower having two corners that are closest to the mower and two corners that are furthest from the mower;  
       (b) a plurality of spaced support wheels carried adjacent at least the two corners of the cutting deck that are furthest from the mower; and  
       (c) a corner suspension connected to at least one of the two corners of the deck that are closest to the mower, wherein the corner suspension comprises at least one upwardly biased connecting link attached to the at least one corner of the cutting deck, the bias on the connecting link being sufficient to elevate the at least one corner of the cutting deck above the ground without using a support wheel adjacent the at least one corner, wherein the connecting link extends substantially vertically and has a lower end and an upper end, wherein the lower end of the connecting link is connected to the cutting deck, wherein the upper end of the connecting link is connected to a spring, and wherein the spring acts between the connecting link and a support arm extending between the mower and the cutting deck, the support arm being pivotally connected at opposite ends to the mower and to the cutting deck.  
     
     
       2. The cutting deck of  claim 1 , further including a pivotal lift arm extending between the mower and the cutting deck for lifting the mower between a lowered operating position and a raised transport position, wherein the support arm is a second support arm that is other than the pivotal lift arm. 
     
     
       3. The cutting deck of  claim 1 , wherein the corner suspension includes a bellcrank pivotally carried on the support arm with the bellcrank having first and second arms, wherein the upper end of the connecting link is connected to the first arm of the bellcrank and the spring has one end thereof connected to the second arm of the bellcrank. 
     
     
       4. The cutting deck of  claim 3 , wherein the spring has a second end anchored on the support arm. 
     
     
       5. The cutting deck of  claim 1 , wherein the support arm has a portion which overlies the cutting deck and is adjacent to the at least one corner of the cutting deck having the corner suspension. 
     
     
       6. The cutting deck of  claim 5 , wherein the corner suspension is connected to the overlying portion of the support arm. 
     
     
       7. The cutting deck of  claim 1 , further including a damper acting between the connecting link and the support arm for reducing bouncing of the cutting deck. 
     
     
       8. The cutting deck of  claim 7 , wherein the damper comprises an oil filled cylinder. 
     
     
       9. The cutting deck of  claim 1 , wherein the corner suspension is provided on only one of the two corners of the cutting deck closest to the mower, the other of the two corners of the cutting deck closest to the mower carrying a support wheel. 
     
     
       10. A rotary cutting deck for a mower, which comprises: 
       (a) a cutting deck having at least one rotary cutting element rotating about a substantially vertical axis in a substantially horizontal cutting plane when the cutting deck and rotary cutting element are in operation;  
       (b) an attachment on the cutting deck for coupling to a pivotal lift arm extending laterally outwardly from one side of the mower, the cutting deck when so coupled to the lift arm having inner front and rear corners that are closest to the mower and outer front and rear corners that are furthest from the mower;  
       (c) three support wheels carried adjacent one of the inner corners, the outer front corner and the outer rear corner of the cutting deck, respectively; and  
       (d) a corner suspension comprising at least one upwardly biased connecting link attached to the other inner corner of the cutting deck, the bias on the connecting link being sufficient to elevate the other inner corner of the cutting deck above the ground without using a support wheel on the other inner corner, wherein the corner suspension includes a pivotal bellcrank having first and second arms, and wherein one end of the connecting link is connected to the first arm of the bellcrank and a spring has one end thereof connected to the second arm of the bellcrank, the spring providing the upward biasing force for the connecting link.  
     
     
       11. The cutting deck of  claim 10 , wherein the one inner corner that carries one of the support wheels is the inner front corner and the other inner corner that carries the corner suspension is the inner rear corner, and wherein the support wheel for the outer rear corner of the cutting deck comprises a caster wheel. 
     
     
       12. The cutting deck of  claim 10 , further including a damper acting on the connecting link for reducing bouncing of the cutting deck. 
     
     
       13. The cutting deck of  claim 10 , further including a support arm extending between the mower and the cutting deck with a portion of the support arm overlying the cutting deck and being adjacent the other inner corner of the cutting deck, wherein the connecting link, bellcrank and spring all overlie the connecting deck with the bellcrank being pivotally carried on the support arm and the spring being anchored an the support arm. 
     
     
       14. The cutting deck of  claim 13 , wherein the support arm is other than the pivotal lift arm. 
     
     
       15. A rotary cutting deck for a mower having a pivotal lift arm for lifting and lowering the cutting deck into and out of engagement with the ground, which comprises: 
       (a) a cutting deck having four corners, the cutting deck having an attachment for coupling to an outer end of the pivotal lift arm of the mower, the attachment being configured to pivotally connect the cutting deck to the lift arm to permit the cutting deck to pivot relative to the lift arm to follow ground contours, and wherein the attachment is located in a central portion of the cutting deck between the four corners of the cutting deck such that the four corners of the cutting deck rise and fall relative to the ground as the cutting deck follows uneven ground contours;  
       (b) ground engaging wheels adjacent three of the four corners of the deck which wheels are adapted to roll over the ground and follow the ground contours; and  
       (c) a corner suspension for the fourth corner of the deck, the corner suspension including an upwardly biased connecting link acting between the mower and the fourth corner of the deck, the connecting link being biased to lift upwardly on the fourth corner of the deck with a biasing force sufficiently strong to elevate the fourth corner of the deck above the ground and to help keep the ground engaging wheels on the other corners of the deck in contact with the ground, the corner suspension taking the place of a ground engaging wheel on the fourth corner of the deck.  
     
     
       16. The cutting deck of  claim 15 , further including a damper acting on the connecting link for reducing bouncing of the cutting deck. 
     
     
       17. The cutting deck of  claim 15 , wherein the attachment is located at the approximate center of the cutting deck.